Look, I’ll be honest with you. The first time someone told me about eSIMs, I nodded along like I understood what they were talking about, then immediately went home and Googled it. Because let’s face it, most of us are still getting our heads around the fact that our phones don’t need physical SIM cards anymore, and now we’re supposed to care about whether they’re “global” or not?

But here’s the thing: if you’re an Aussie who travels overseas with any sort of regularity, understanding eSIMs might actually save you a decent chunk of money. And given what international roaming used to cost us, that’s worth paying attention to.

The Old Way Was Expensive (And We All Know It)

Remember the dark days of international roaming? You’d land in Bali or Bangkok, turn on your phone, and immediately get that text from your telco cheerfully informing you that data now costs $10 per megabyte or some equally horrifying number. Then you’d spend your entire holiday in airplane mode, hunting down WiFi like some sort of digital nomad, just to send a photo to your mum proving you’re still alive.

The alternative was buying a local SIM card, which meant finding a phone shop that didn’t look too dodgy, somehow communicating what you needed, and then carefully storing your Australian SIM card in your wallet where you’d inevitably lose it somewhere between the hotel safe and your dirty laundry.

Neither option was great.

So What Actually Is a Global eSIM?

Right, so an eSIM is basically a digital SIM card that’s already embedded in your phone. Instead of physically swapping out a little chip, you just download a profile and activate it. Global eSIMs are the ones that work across multiple countries, so you’re not buying a new one every time you cross a border.

Simple enough. The question is whether they actually save you money compared to what you’d normally spend.

Breaking Down the Numbers

Here’s where it gets interesting. Let’s say you’re doing a two-week trip through Europe, visiting three or four countries. With a global eSIM from providers like Airalo, Holafly, or Nomad, you’re looking at somewhere between $15 to $50 AUD for anywhere from 3GB to unlimited data, depending on the provider and package.

Compare that to what Telstra, Optus, or Vodafone charge for their international roaming day passes. Telstra’s currently sitting at $10 per day for their international roaming in most countries. That’s $140 for a two-week trip. Optus has similar pricing. Even if you’re selective about which days you activate it, you’re still looking at easily over $100.

The maths isn’t exactly complicated.

But There Are Catches (Because There Always Are)

Before you rush off to download every eSIM app in existence, let’s talk about the limitations.

First up, you lose your Australian phone number while the eSIM is active. That means if someone calls your regular number, it’s going straight to voicemail. For some people, that’s fine. For others who need to be contactable for work or family emergencies, it’s a dealbreaker. Some newer phones let you run dual SIMs (your regular one and an eSIM), which solves this problem, but not all devices support it.

Second, not all phones work with eSIMs. If you’re rocking an older iPhone (pre-XS) or an Android that’s a few years old, you’re out of luck. You’ll need to check whether your specific model supports eSIM technology before you start planning around it.

Third, the data speeds can be… variable. Some global eSIM providers use local network infrastructure that isn’t exactly premium tier. It’ll work fine for maps and messaging, but if you’re trying to upload 4K video to Instagram from a hilltop in Santorini, you might be disappointed.

When eSIMs Make the Most Sense

If you’re doing a trip that involves multiple countries, global eSIMs are genuinely brilliant. Hopping from Italy to Greece to Croatia? Your eSIM just works in all three. No airport SIM card purchases, no fiddling with settings every time you cross a border.

They’re also perfect for shorter trips where you don’t want to commit to a 30-day local SIM card. Three days in Singapore for work? A week in Tokyo? Just grab a short-term eSIM package and you’re sorted.

And for anyone who travels frequently for work, having an eSIM as a backup option is just smart planning. Your regular roaming isn’t working properly? Switch to your eSIM. Hotel WiFi is abysmal? eSIM. It’s basically travel insurance for your internet connection.

When You Might Skip Them

If you’re going to one country for an extended period, a local SIM card is probably still your best bet. Spending a month in Vietnam? Just get a Vietnamese SIM. It’ll be cheaper than any global eSIM for that duration, and you’ll get better speeds and coverage.

Same goes if you absolutely need your Australian phone number to remain active. Business calls, family emergencies, two-factor authentication for your banking apps – if any of these are critical, you’ll want to stick with your regular carrier’s roaming or use a dual-SIM setup.

The Verdict for Aussie Travellers

Do global eSIMs save money? For most people, yes. Especially if you’re doing multi-country trips or shorter holidays where telco roaming charges would add up quickly.

Are they perfect? No. There are limitations around phone number accessibility, device compatibility, and occasional network quality issues.

But here’s the reality: international travel is expensive enough without paying $10 a day just to check Google Maps and upload photos. Global eSIMs give you decent connectivity at a fraction of what Australian telcos charge for roaming, and that’s worth considering.

My advice? Try one on your next trip. Pick a reputable provider, buy a small package, and see how it goes. Worst case scenario, it doesn’t work out and you fall back to WiFi hunting. Best case, you’ve just found a way to save yourself a hundred bucks or more every time you leave the country.

And honestly, that’s enough for at least a few extra cocktails at the hotel bar. Which is the whole point of travelling in the first place, isn’t it?